1. Field of the Invention
The present invention relates to an image and audio playback technology in a mobile communication terminal and, more particularly, to a technology in which a single image is divided into two halves, i.e., a left-half image and a right-half image, which are displayed on two mobile communication terminals, respectively, and, in addition, left-side and right-side audio data composing stereo audio data can be played in two mobile communication terminals, respectively, according to the relative locations of the two mobile communication terminals.
2. Description of Related Art
With the development of wireless/wireline telecommunication technologies, users can enjoy various kinds of contents through mobile communication terminals. Examples of the content include content offered through mobile communications (photos, moving pictures, animation, games, bell sounds, sound sources, etc.), and content offered through a cable connection between a personal computer and a mobile communication terminal. In addition, users using mobile communication terminals with a camera function can view content such as photos or moving pictures taken by the mobile communication terminals through their own mobile communication terminals.
Further, mobile communication terminals with a broadcast receiving function have been recently released onto the market. Examples of broadcast channels include over-the-air broadcast, such as TV and radio, and digital broadcast channels. The users can view such broadcast content through the mobile communication terminals.
The users can view image content realistically through a mobile communication terminal with a display device as wide as possible. However, there is a problem in that the mobile communication terminal has a limitation in size.
Korean Unexamined Patent Application Publication No. 2004-75433 discloses a technology to overcome such a problem. According to the technology, two mobile communication terminals receive two divided image files, respectively, which are in turn displayed to form a single full screen. A detailed description thereof will now be given.
According to the above-mentioned publication, there is provided a method of forming a single full-screen image through two mobile communication terminals which receive two image files obtained by dividing the single full-screen image file into two halves, the method including the steps of: (a) transmitting the two image files from a server with a shared key having the two image files to the two mobile communication terminals, respectively, where the two image files form a single full-screen image, (b) requesting the shared key from the server and receiving the shared key at any one of the mobile communication terminals having received the image files, (c) transmitting the shared key input to any one of the mobile communication terminals to another adjacent mobile communication terminal, and (d) transmitting a simultaneous execution signal from the mobile communication terminal having received the shared key to the other mobile communication terminal.
As a result, the two divided images simultaneously displayed on the two mobile communication terminals forms a single full-screen image. In an embodiment, the adjacent mobile communication terminals are communicated with each other using infrared data association. In step (c), when the shared key is input to the mobile communication terminal, the inputted shared key is compared with a shared key of the transmitted image file. When they are determined to match each other, the image file is transmitted to an adjacent other mobile communication terminal.
A more detailed description of the technology described in the above publication will now be given in consideration of a method of implementing a division playback function, available content range, convenience, and the like.
According to the above-mentioned publication, a communication service provider or content provider divides a single image file into left-half and right-half screen images, which are in turn encoded. Two mobile communication terminals download the left-half and right-half screen images, respectively, and play the respective screen images. The two terminals have only to set the playback time for the two screen image files so that the two screen image files can be simultaneously played. That is, the terminals have their respective screen image files and play the screen image files by transmitting a start signal to each other through infrared data association so as to set the playback start time for the respective image files.
If the above-mentioned method is applied to general image files rather than the divided screen image files, the same images will be simultaneously displayed on the two terminals as in a multi-vision TV. Thus, the technology disclosed in the above publication corresponds to a technology related to an image service, one of mobile services, rather than a technology realized in the mobile communication terminal.
In addition, according to the above-mentioned publication, mobile carriers or service providers should create left-half and right-half image files. That is, a single image file is divided into two halves, i.e., left-half and right-half screen image data, each of which is in turn separately encoded and then transmitted to a different one of two terminals. Thus, the service providers should perform the above-mentioned operations for all the image files used by general users and store the two divided image files for a few users using the above service.
In addition, the divided image files are not played in real time. In more detail, the two terminals download their respective left-half and right-half image files. Next, any one of the two terminals downloads a shared key. The two terminals set a timing using the shared key and play the two divided image files simultaneously. Thus, since the two image files are played back after they are downloaded and the shared key is received, the image files cannot be played in real time. Further, it is meaningless that only a single terminal plays an image file stored therein.
Meanwhile, the above-mentioned publication does not disclose a method of processing audio data when content is played using two mobile communication terminals. The audio data may exist alone in the form of an MP3 file, or exist in combination with image data such as MPEG4 data.
Recently released mobile communication terminals offer a stereo output function. Accordingly, users can enjoy audio in stereo sound through earphones or speakers provided in the mobile communication terminals.